The present invention relates to communications and more particularly wireless communication systems.
The functionality of cellular telephones and other hand-held communication devices has been increasing rapidly. Internet enabled cellular phones and personal digital assistants (PDAs) that can communicate via the internet are now in widespread use.
A variety of digital communication protocols have been developed. A number of non-compatible communication protocols and air interfaces such as PDC/PHS, TDMA, CDMA, GSM and IEEE 802.11x have each been deployed in the market. However no protocol is ubiquitous. In fact many communication systems incorporate one or more of these protocols to deliver services to their customers.
Third generation wireless protocols that handle voice, video and data are being developed. The third generation protocols are designed to handle voice, video, and data communication over devices such as cellular phones, PDAs and laptop computers.
A typical hand held communication device (e.g. cellular phone or PDA) is relatively complex. Almost all handheld communication devices include a keypad/keyboard and also include a display device (of varying resolution), which may in many cases be a touch-screen. The technical complexities of these handheld devices make them relatively expensive. In order to encourage widespread usage of such communication devices, some network service providers subsidize the cost of these hand-held communication devices.
Additionally because of the difference in the feature sets and processing power available in these communication devices, there is no efficient and low cost method to deliver standard content to all devices. A number of attempts such as the Wireless Application Protocol have been created. WAP requires the execution of a browser on the cellular phone or PDAs. This browser then makes custom requests to the target web applications. The web application also needs to be modified to format the content to match the capabilities of the hand-held device in use. Rewriting and reformatting of content is an impediment to the deployment of a variety of applications to customers. The requirement to execute a browser on the hand-held device generally requires a processor, large memory, a display etc. adding to the cost of the device. It also results in relatively large power consumption leading to relatively short battery life.
The architecture for a typical prior art handheld mobile device is shown in FIG. 1. The components of a typical prior art handheld device include a microprocessor 185 and associated RAM and Flash memory 184. The microprocessor 185 executes the resident software and controls the input/output devices. The input/output devices include devices such as microphone/speaker 183, keypad/board 181, display device 182, a codex 186, a radio transceiver 189 and often a DSP 187 for analog signal processing. In view of the number of components and the complexity prior art handheld devices are relatively expensive and they use a relatively large amount of power.
The present invention is directed to a system and method which will accommodate relatively low cost hand held devices that use a relatively small amount of power.
The present invention provides a system that can accommodate very simple, low cost portable (i.e. hand held) devices that use a very small amount of power. The system includes a central server, that runs a variety of applications and which has a module associated with each portable device. Each portable device communicates with its associated module using wireless communication and the well known Internet Protocol (IP) that has been developed for the internet. With the present invention the portable device merely sends and receives IP packets. The portable device does not include a browser.
The present invention provides an Internet Protocol based system and method that may be implemented over a heterogeneous wireless communication network. A system operating in accordance with the present invention includes:
1. A set of hardware components that enable radio communication and IP packetization. The system includes a Software Defined Radio (SDR) and Application Specific Device (ASD) modules.
2. Matching software protocol programs: The system includes a Client Proxy Server (CPS) and a Device Personality Object (DPO) program pair that executes at an Application Server (AS). The CPS/DPO program pair abstracts all the device dependencies from the application and uniquely maps the mobile access device to the target application. The CPS/DPO program pair contains all of the information required to map content and translate requests to and from the application and to the accessing mobile device. There is a unique CPS/DPO program pair for each mobile device that is active.
Data is exchanged between the hand-held communication devices and cellular wireless base stations using IP data packets. All devices can use this IP packet transmission protocol to allow for frequency sharing and compatibility with existing internet infrastructure.
The system can include very small, very low power hand-held devices, that do not include a dial/key pad, large data storage or a complex microprocessor based platform and can be low cost and low power devices.
Each hand-held device is logged into the internet via the base station and results in the spawning of a CPS/DPO program pair at the Application Server (AS) where the target application resides. CPS establishes a session for each remote wireless device. A single CPS can have multiple DPOs, each DPO being a plug-in software object. The DPO is responsible for translating the device requests to the application in use and also for translating the applications responses to the appropriate format required by the requesting mobile device. A very small footprint or xe2x80x9clightweightxe2x80x9d software component is embedded in each hand-held device and is responsible for IP packet management.
The Application server is typically a large computer with enormous power. By executing this complex code i.e. the CPS/DPO combination, at the Application Server it is possible to provide rich applications to simple, low-cost mobile or handheld devices. The cost of complex microprocessor based devices may be dispensed with. This enables the manufacture and deployment of very low-cost wireless hand-held devices for Internet access. The computational capability at the AS is generally capable of handling thousands of such CPS/DPO sessions in parallel enabling a practical way to deploy services.
This method also enables rapid deployment of applications by simply deploying the appropriate DPO for a particular mobile device class at the xe2x80x9chead endxe2x80x9d of the network i.e. at the AS. This ability to harness the computing power of the Application Server also results in better security, customer experience etc.